1
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Nahar R, Zhai W, Zhang T, Takano A, Khng AJ, Lee YY, Liu X, Lim CH, Koh TPT, Aung ZW, Lim TKH, Veeravalli L, Yuan J, Teo ASM, Chan CX, Poh HM, Chua IML, Liew AA, Lau DPX, Kwang XL, Toh CK, Lim WT, Lim B, Tam WL, Tan EH, Hillmer AM, Tan DSW. Elucidating the genomic architecture of Asian EGFR-mutant lung adenocarcinoma through multi-region exome sequencing. Nat Commun 2018; 9:216. [PMID: 29335443 PMCID: PMC5768770 DOI: 10.1038/s41467-017-02584-z] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 12/11/2017] [Indexed: 12/14/2022] Open
Abstract
EGFR-mutant lung adenocarcinomas (LUAD) display diverse clinical trajectories and are characterized by rapid but short-lived responses to EGFR tyrosine kinase inhibitors (TKIs). Through sequencing of 79 spatially distinct regions from 16 early stage tumors, we show that despite low mutation burdens, EGFR-mutant Asian LUADs unexpectedly exhibit a complex genomic landscape with frequent and early whole-genome doubling, aneuploidy, and high clonal diversity. Multiple truncal alterations, including TP53 mutations and loss of CDKN2A and RB1, converge on cell cycle dysregulation, with late sector-specific high-amplitude amplifications and deletions that potentially beget drug resistant clones. We highlight the association between genomic architecture and clinical phenotypes, such as co-occurring truncal drivers and primary TKI resistance. Through comparative analysis with published smoking-related LUAD, we postulate that the high intra-tumor heterogeneity observed in Asian EGFR-mutant LUAD may be contributed by an early dominant driver, genomic instability, and low background mutation rates. EGFR mutant lung adenocarcinoma (LUAD) exhibit diverse clinical outcomes in response to targeted therapies. Here the authors show that these LUADs involve a complex genomic landscape with high intratumor heterogeneity, providing insights into the evolutionary trajectory of oncogene-driven LUAD and potential mediators of EGFR TKI resistance.
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Affiliation(s)
- Rahul Nahar
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Weiwei Zhai
- Human Genetics, Genome Institute of Singapore, Singapore, 138672, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Tong Zhang
- Human Genetics, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Angela Takano
- Department of Pathology, Singapore General Hospital, Singapore, 169608, Singapore
| | - Alexis J Khng
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Yin Yeng Lee
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Xingliang Liu
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Chong Hee Lim
- Department of Cardiothoracic Surgery, National Heart Centre Singapore, Singapore, 169609, Singapore
| | - Tina P T Koh
- Department of Cardiothoracic Surgery, National Heart Centre Singapore, Singapore, 169609, Singapore
| | - Zaw Win Aung
- Division of Clinical Trials and Epidemiological Sciences, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Tony Kiat Hon Lim
- Department of Pathology, Singapore General Hospital, Singapore, 169608, Singapore
| | - Lavanya Veeravalli
- Research Pipeline Development, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Ju Yuan
- Cancer Stem Cell Biology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Audrey S M Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Cheryl X Chan
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Huay Mei Poh
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Ivan M L Chua
- Next Generation Sequencing Platform, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Audrey Ann Liew
- Cancer Stem Cell Biology, Genome Institute of Singapore, Singapore, 138672, Singapore.,Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore.,Cancer Therapeutics Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Dawn Ping Xi Lau
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore.,Cancer Therapeutics Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Xue Lin Kwang
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore.,Cancer Therapeutics Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Chee Keong Toh
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Wan-Teck Lim
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Bing Lim
- Cancer Stem Cell Biology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Wai Leong Tam
- Cancer Stem Cell Biology, Genome Institute of Singapore, Singapore, 138672, Singapore
| | - Eng-Huat Tan
- Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore
| | - Axel M Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, 138672, Singapore. .,Institute of Pathology, University Hospital Cologne, 50937, Cologne, Germany.
| | - Daniel S W Tan
- Cancer Stem Cell Biology, Genome Institute of Singapore, Singapore, 138672, Singapore. .,Division of Medical Oncology, National Cancer Centre Singapore, Singapore, 169610, Singapore. .,Cancer Therapeutics Research Laboratory, Division of Medical Sciences, National Cancer Centre Singapore, Singapore, 169610, Singapore.
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2
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Ribi S, Baumhoer D, Lee K, Edison, Teo ASM, Madan B, Zhang K, Kohlmann WK, Yao F, Lee WH, Hoi Q, Cai S, Woo XY, Tan P, Jundt G, Smida J, Nathrath M, Sung WK, Schiffman JD, Virshup DM, Hillmer AM. TP53 intron 1 hotspot rearrangements are specific to sporadic osteosarcoma and can cause Li-Fraumeni syndrome. Oncotarget 2016; 6:7727-40. [PMID: 25762628 PMCID: PMC4480712 DOI: 10.18632/oncotarget.3115] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 01/08/2015] [Indexed: 12/05/2022] Open
Abstract
Somatic mutations of TP53 are among the most common in cancer and germline mutations of TP53 (usually missense) can cause Li-Fraumeni syndrome (LFS). Recently, recurrent genomic rearrangements in intron 1 of TP53 have been described in osteosarcoma (OS), a highly malignant neoplasm of bone belonging to the spectrum of LFS tumors. Using whole-genome sequencing of OS, we found features of TP53 intron 1 rearrangements suggesting a unique mechanism correlated with transcription. Screening of 288 OS and 1,090 tumors of other types revealed evidence for TP53 rearrangements in 46 (16%) OS, while none were detected in other tumor types, indicating this rearrangement to be highly specific to OS. We revisited a four-generation LFS family where no TP53 mutation had been identified and found a 445 kb inversion spanning from the TP53 intron 1 towards the centromere. The inversion segregated with tumors in the LFS family. Cancers in this family had loss of heterozygosity, retaining the rearranged allele and resulting in TP53 expression loss. In conclusion, intron 1 rearrangements cause p53-driven malignancies by both germline and somatic mechanisms and provide an important mechanism of TP53 inactivation in LFS, which might in part explain the diagnostic gap of formerly classified “TP53 wild-type” LFS.
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Affiliation(s)
- Sebastian Ribi
- Cancer Therapeutics & Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Daniel Baumhoer
- Bone Tumor Reference Center at The Institute of Pathology, University Hospital Basel, CH-4003 Basel, Switzerland.,Clinical Cooperation Group Osteosarcoma, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg, Germany
| | - Kristy Lee
- Department of Pediatrics and Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Edison
- Duke-NUS Graduate Medical School Singapore, Singapore 169857, Singapore
| | - Audrey S M Teo
- Cancer Therapeutics & Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Babita Madan
- Duke-NUS Graduate Medical School Singapore, Singapore 169857, Singapore
| | - Kang Zhang
- Institute for Genomic Medicine, UC San Diego, La Jolla, CA 92830, USA
| | - Wendy K Kohlmann
- Huntsman Cancer Institute, University of Utah Health Care, Utah, UT 84112, USA
| | - Fei Yao
- Cancer Therapeutics & Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Wah Heng Lee
- Computational & Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Qiangze Hoi
- Computational & Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Shaojiang Cai
- Computational & Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Xing Yi Woo
- Personal Genomics Solutions, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Patrick Tan
- Cancer Therapeutics & Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore.,Duke-NUS Graduate Medical School Singapore, Singapore 169857, Singapore.,Cancer Science Institute of Singapore, National University of Singapore, Singapore 117599, Singapore
| | - Gernot Jundt
- Bone Tumor Reference Center at The Institute of Pathology, University Hospital Basel, CH-4003 Basel, Switzerland
| | - Jan Smida
- Clinical Cooperation Group Osteosarcoma, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg, Germany.,Department of Pediatrics and Wilhelm Sander Sarcoma Treatment Unit, Technische Universität München and Pediatric Oncology Center, 81675 Munich, Germany
| | - Michaela Nathrath
- Clinical Cooperation Group Osteosarcoma, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg, Germany.,Department of Pediatrics and Wilhelm Sander Sarcoma Treatment Unit, Technische Universität München and Pediatric Oncology Center, 81675 Munich, Germany
| | - Wing-Kin Sung
- Computational & Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore.,School of Computing, National University of Singapore, Singapore 117417, Singapore
| | - Joshua D Schiffman
- Department of Pediatrics and Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - David M Virshup
- Duke-NUS Graduate Medical School Singapore, Singapore 169857, Singapore
| | - Axel M Hillmer
- Cancer Therapeutics & Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
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3
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Verzotto D, M. Teo AS, Hillmer AM, Nagarajan N. OPTIMA: sensitive and accurate whole-genome alignment of error-prone genomic maps by combinatorial indexing and technology-agnostic statistical analysis. Gigascience 2016; 5:2. [PMID: 26793302 PMCID: PMC4719737 DOI: 10.1186/s13742-016-0110-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 01/06/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Resolution of complex repeat structures and rearrangements in the assembly and analysis of large eukaryotic genomes is often aided by a combination of high-throughput sequencing and genome-mapping technologies (for example, optical restriction mapping). In particular, mapping technologies can generate sparse maps of large DNA fragments (150 kilo base pairs (kbp) to 2 Mbp) and thus provide a unique source of information for disambiguating complex rearrangements in cancer genomes. Despite their utility, combining high-throughput sequencing and mapping technologies has been challenging because of the lack of efficient and sensitive map-alignment algorithms for robustly aligning error-prone maps to sequences. RESULTS We introduce a novel seed-and-extend glocal (short for global-local) alignment method, OPTIMA (and a sliding-window extension for overlap alignment, OPTIMA-Overlap), which is the first to create indexes for continuous-valued mapping data while accounting for mapping errors. We also present a novel statistical model, agnostic with respect to technology-dependent error rates, for conservatively evaluating the significance of alignments without relying on expensive permutation-based tests. CONCLUSIONS We show that OPTIMA and OPTIMA-Overlap outperform other state-of-the-art approaches (1.6-2 times more sensitive) and are more efficient (170-200 %) and precise in their alignments (nearly 99 % precision). These advantages are independent of the quality of the data, suggesting that our indexing approach and statistical evaluation are robust, provide improved sensitivity and guarantee high precision.
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Affiliation(s)
- Davide Verzotto
- Computational and Systems Biology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Audrey S. M. Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Axel M. Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Niranjan Nagarajan
- Computational and Systems Biology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
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4
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Teo ASM, Verzotto D, Yao F, Nagarajan N, Hillmer AM. Single-molecule optical genome mapping of a human HapMap and a colorectal cancer cell line. Gigascience 2015; 4:65. [PMID: 26719794 PMCID: PMC4696294 DOI: 10.1186/s13742-015-0106-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 12/17/2015] [Indexed: 11/21/2022] Open
Abstract
Background Next-generation sequencing (NGS) technologies have changed our understanding of the variability of the human genome. However, the identification of genome structural variations based on NGS approaches with read lengths of 35–300 bases remains a challenge. Single-molecule optical mapping technologies allow the analysis of DNA molecules of up to 2 Mb and as such are suitable for the identification of large-scale genome structural variations, and for de novo genome assemblies when combined with short-read NGS data. Here we present optical mapping data for two human genomes: the HapMap cell line GM12878 and the colorectal cancer cell line HCT116. Findings High molecular weight DNA was obtained by embedding GM12878 and HCT116 cells, respectively, in agarose plugs, followed by DNA extraction under mild conditions. Genomic DNA was digested with KpnI and 310,000 and 296,000 DNA molecules (≥150 kb and 10 restriction fragments), respectively, were analyzed per cell line using the Argus optical mapping system. Maps were aligned to the human reference by OPTIMA, a new glocal alignment method. Genome coverage of 6.8× and 5.7× was obtained, respectively; 2.9× and 1.7× more than the coverage obtained with previously available software. Conclusions Optical mapping allows the resolution of large-scale structural variations of the genome, and the scaffold extension of NGS-based de novo assemblies. OPTIMA is an efficient new alignment method; our optical mapping data provide a resource for genome structure analyses of the human HapMap reference cell line GM12878, and the colorectal cancer cell line HCT116.
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Affiliation(s)
- Audrey S M Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Davide Verzotto
- Computational and Systems Biology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Fei Yao
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Niranjan Nagarajan
- Computational and Systems Biology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
| | - Axel M Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, 60 Biopolis Street, Singapore, 138672 Singapore
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5
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Yao F, Kausalya JP, Sia YY, Teo ASM, Lee WH, Ong AGM, Zhang Z, Tan JHJ, Li G, Bertrand D, Liu X, Poh HM, Guan P, Zhu F, Pathiraja TN, Ariyaratne PN, Rao J, Woo XY, Cai S, Mulawadi FH, Poh WT, Veeravalli L, Chan CS, Lim SS, Leong ST, Neo SC, Choi PSD, Chew EGY, Nagarajan N, Jacques PÉ, So JBY, Ruan X, Yeoh KG, Tan P, Sung WK, Hunziker W, Ruan Y, Hillmer AM. Recurrent Fusion Genes in Gastric Cancer: CLDN18-ARHGAP26 Induces Loss of Epithelial Integrity. Cell Rep 2015; 12:272-85. [PMID: 26146084 DOI: 10.1016/j.celrep.2015.06.020] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 04/21/2015] [Accepted: 06/06/2015] [Indexed: 12/21/2022] Open
Abstract
Genome rearrangements, a hallmark of cancer, can result in gene fusions with oncogenic properties. Using DNA paired-end-tag (DNA-PET) whole-genome sequencing, we analyzed 15 gastric cancers (GCs) from Southeast Asians. Rearrangements were enriched in open chromatin and shaped by chromatin structure. We identified seven rearrangement hot spots and 136 gene fusions. In three out of 100 GC cases, we found recurrent fusions between CLDN18, a tight junction gene, and ARHGAP26, a gene encoding a RHOA inhibitor. Epithelial cell lines expressing CLDN18-ARHGAP26 displayed a dramatic loss of epithelial phenotype and long protrusions indicative of epithelial-mesenchymal transition (EMT). Fusion-positive cell lines showed impaired barrier properties, reduced cell-cell and cell-extracellular matrix adhesion, retarded wound healing, and inhibition of RHOA. Gain of invasion was seen in cancer cell lines expressing the fusion. Thus, CLDN18-ARHGAP26 mediates epithelial disintegration, possibly leading to stomach H(+) leakage, and the fusion might contribute to invasiveness once a cell is transformed.
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Affiliation(s)
- Fei Yao
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore; The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore
| | - Jaya P Kausalya
- Epithelial Cell Biology Laboratory, Institute of Molecular and Cell Biology, Singapore 138673, Singapore
| | - Yee Yen Sia
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore; The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore
| | - Audrey S M Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore; The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore
| | - Wah Heng Lee
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Alicia G M Ong
- Epithelial Cell Biology Laboratory, Institute of Molecular and Cell Biology, Singapore 138673, Singapore
| | - Zhenshui Zhang
- Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Joanna H J Tan
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Guoliang Li
- National Key Laboratory of Crop Genetic Improvement, Center for Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan 430070, China
| | - Denis Bertrand
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Xingliang Liu
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Huay Mei Poh
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Peiyong Guan
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore; School of Computing, National University of Singapore, Singapore 117417, Singapore
| | - Feng Zhu
- The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
| | - Thushangi Nadeera Pathiraja
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore; The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore
| | - Pramila N Ariyaratne
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Jaideepraj Rao
- Department of General Surgery, Tan Tock Seng Hospital, Singapore 308433, Singapore
| | - Xing Yi Woo
- Personal Genomic Solutions, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Shaojiang Cai
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Fabianus H Mulawadi
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Wan Ting Poh
- Personal Genomic Solutions, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Lavanya Veeravalli
- Research Computing, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Chee Seng Chan
- Research Computing, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Seong Soo Lim
- Human Genetics, Genome Institute of Singapore, Singapore 138672, Singapore
| | - See Ting Leong
- Genome Technology and Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Say Chuan Neo
- Genome Technology and Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Poh Sum D Choi
- Genome Technology and Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Elaine G Y Chew
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Niranjan Nagarajan
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | | | - Jimmy B Y So
- The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore; Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; National University Health System, Singapore 119228, Singapore
| | - Xiaoan Ruan
- Personal Genomic Solutions, Genome Institute of Singapore, Singapore 138672, Singapore; Genome Technology and Biology, Genome Institute of Singapore, Singapore 138672, Singapore
| | - Khay Guan Yeoh
- The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore; National University Health System, Singapore 119228, Singapore
| | - Patrick Tan
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore; The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore; Duke-NUS Graduate Medical School, Singapore 169857, Singapore; Cancer Science Institute of Singapore, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117599, Singapore
| | - Wing-Kin Sung
- Computational and Systems Biology, Genome Institute of Singapore, Singapore 138672, Singapore; School of Computing, National University of Singapore, Singapore 117417, Singapore
| | - Walter Hunziker
- Epithelial Cell Biology Laboratory, Institute of Molecular and Cell Biology, Singapore 138673, Singapore; Department of Physiology, National University of Singapore, Singapore 117597, Singapore.
| | - Yijun Ruan
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA.
| | - Axel M Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore 138672, Singapore; The Singapore Gastric Cancer Consortium, National University of Singapore, Singapore 119228, Singapore.
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6
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Arteaga ME, Hunziker W, Teo ASM, Hillmer AM, Mutchinick OM. Familial hypomagnesemia with hypercalciuria and nephrocalcinosis: variable phenotypic expression in three affected sisters from Mexican ancestry. Ren Fail 2014; 37:180-3. [PMID: 25366522 DOI: 10.3109/0886022x.2014.977141] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Familial hypomagnesemia with hypercalciuria and nephrocalcinosis is a rare autosomal recessive renal disease caused by mutations in genes for the tight junction transmembrane proteins Claudin-16 (CLDN16) and Claudin-19 (CLDN19). We present the first case report of a Mexican family with three affected sisters carrying a p.Gly20Asp mutation in CLDN19 whose heterozygous mother showed evident hypercalciuria and normal low magnesemia without any other clinical, laboratory, and radiological symptoms of renal disease making of her an unsuitable donor. The affected sisters showed variable phenotypic expression including age of first symptoms, renal urinary tract infections, nephrolithiasis, nephrocalcinosis, and eye symptoms consisting in retinochoroiditis, strabismus, macular scars, bilateral anisocoria, and severe myopia and astigmatism. End stage renal disease due to renal failure needed kidney transplantation in the three of them. Interesting findings were a heterozygous mother with asymptomatic hypercalciuria warning on the need of carefully explore clinical, laboratory, kidney ultrasonograpy, and mutation status in first degree asymptomatic relatives to avoid inappropriate kidney donors; an evident variable phenotypic expression among patients; the identification of a mutation almost confined to Spanish cases and a 3.5 Mb block of genomic homozygosis strongly suggesting a common remote parental ancestor for the gene mutation reported.
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Affiliation(s)
- María E Arteaga
- Department of Genetics, National Institute of Medical Sciences and Nutrition "Salvador Zubirán" , México City , México
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7
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Krishnan VG, Ebert PJ, Ting JC, Lim E, Wong SS, Teo ASM, Yue YG, Chua HH, Ma X, Loh GSL, Lin Y, Tan JHJ, Yu K, Zhang S, Reinhard C, Tan DSW, Peters BA, Lincoln SE, Ballinger DG, Laramie JM, Nilsen GB, Barber TD, Tan P, Hillmer AM, Ng PC. Whole-genome sequencing of asian lung cancers: second-hand smoke unlikely to be responsible for higher incidence of lung cancer among Asian never-smokers. Cancer Res 2014; 74:6071-81. [PMID: 25189529 DOI: 10.1158/0008-5472.can-13-3195] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Asian nonsmoking populations have a higher incidence of lung cancer compared with their European counterparts. There is a long-standing hypothesis that the increase of lung cancer in Asian never-smokers is due to environmental factors such as second-hand smoke. We analyzed whole-genome sequencing of 30 Asian lung cancers. Unsupervised clustering of mutational signatures separated the patients into two categories of either all the never-smokers or all the smokers or ex-smokers. In addition, nearly one third of the ex-smokers and smokers classified with the never-smoker-like cluster. The somatic variant profiles of Asian lung cancers were similar to that of European origin with G.C>T.A being predominant in smokers. We found EGFR and TP53 to be the most frequently mutated genes with mutations in 50% and 27% of individuals, respectively. Among the 16 never-smokers, 69% had an EGFR mutation compared with 29% of 14 smokers/ex-smokers. Asian never-smokers had lung cancer signatures distinct from the smoker signature and their mutation profiles were similar to European never-smokers. The profiles of Asian and European smokers are also similar. Taken together, these results suggested that the same mutational mechanisms underlie the etiology for both ethnic groups. Thus, the high incidence of lung cancer in Asian never-smokers seems unlikely to be due to second-hand smoke or other carcinogens that cause oxidative DNA damage, implying that routine EGFR testing is warranted in the Asian population regardless of smoking status.
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Affiliation(s)
- Vidhya G Krishnan
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | | | | | - Elaine Lim
- Medical Oncology, Mount Elizabeth Medical Centre, Mount Elizabeth, Singapore. Medical Oncology, Tan Tock Seng Hospital, Singapore, Singapore; Medical Oncology, National University Hospital, Singapore, Singapore
| | | | - Audrey S M Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Yong G Yue
- Lilly Corporate Center, Indianapolis, Indiana
| | - Hui-Hoon Chua
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Xiwen Ma
- Lilly Corporate Center, Indianapolis, Indiana
| | - Gary S L Loh
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Yuhao Lin
- Lilly Corporate Center, Indianapolis, Indiana
| | - Joanna H J Tan
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore.
| | - Kun Yu
- Lilly Corporate Center, Indianapolis, Indiana
| | - Shenli Zhang
- Genomic Oncology, Duke-NUS Graduate Medical School, Singapore, Singapore
| | | | - Daniel S W Tan
- Department of Medical Oncology, National Cancer Centre Singapore, Singapore, Singapore
| | | | | | | | | | | | | | - Patrick Tan
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore. Genomic Oncology, Duke-NUS Graduate Medical School, Singapore, Singapore. Cancer Science Institute of Singapore, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; Cellular and Molecular Research, National Cancer Centre, Singapore, Singapore
| | - Axel M Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore.
| | - Pauline C Ng
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore.
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8
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Inaki K, Menghi F, Woo XY, Wagner JP, Jacques PÉ, Lee YF, Shreckengast PT, Soon WW, Malhotra A, Teo ASM, Hillmer AM, Khng AJ, Ruan X, Ong SH, Bertrand D, Nagarajan N, Karuturi RKM, Miranda AH, Liu ET. Systems consequences of amplicon formation in human breast cancer. Genome Res 2014; 24:1559-71. [PMID: 25186909 PMCID: PMC4199368 DOI: 10.1101/gr.164871.113] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chromosomal structural variations play an important role in determining the transcriptional landscape of human breast cancers. To assess the nature of these structural variations, we analyzed eight breast tumor samples with a focus on regions of gene amplification using mate-pair sequencing of long-insert genomic DNA with matched transcriptome profiling. We found that tandem duplications appear to be early events in tumor evolution, especially in the genesis of amplicons. In a detailed reconstruction of events on chromosome 17, we found large unpaired inversions and deletions connect a tandemly duplicated ERBB2 with neighboring 17q21.3 amplicons while simultaneously deleting the intervening BRCA1 tumor suppressor locus. This series of events appeared to be unusually common when examined in larger genomic data sets of breast cancers albeit using approaches with lesser resolution. Using siRNAs in breast cancer cell lines, we showed that the 17q21.3 amplicon harbored a significant number of weak oncogenes that appeared consistently coamplified in primary tumors. Down-regulation of BRCA1 expression augmented the cell proliferation in ERBB2-transfected human normal mammary epithelial cells. Coamplification of other functionally tested oncogenic elements in other breast tumors examined, such as RIPK2 and MYC on chromosome 8, also parallel these findings. Our analyses suggest that structural variations efficiently orchestrate the gain and loss of cancer gene cassettes that engage many oncogenic pathways simultaneously and that such oncogenic cassettes are favored during the evolution of a cancer.
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Affiliation(s)
- Koichiro Inaki
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore; The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06030, USA
| | - Francesca Menghi
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore; The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06030, USA
| | - Xing Yi Woo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Joel P Wagner
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore; The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06030, USA; Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Pierre-Étienne Jacques
- Computational and Systems Biology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore; Université de Sherbrooke, Sherbrooke, Québec, J1K 2R1, Canada
| | - Yi Fang Lee
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | | | - Wendy WeiJia Soon
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Ankit Malhotra
- The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06030, USA
| | - Audrey S M Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Axel M Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Alexis Jiaying Khng
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Xiaoan Ruan
- Genome Technology and Biology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Swee Hoe Ong
- Computational and Systems Biology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Denis Bertrand
- Computational and Systems Biology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - Niranjan Nagarajan
- Computational and Systems Biology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore
| | - R Krishna Murthy Karuturi
- Computational and Systems Biology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore; The Jackson Laboratory, Bar Harbor, Maine 04609, USA
| | | | - Edison T Liu
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Genome, Singapore 138672, Singapore; The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06030, USA; The Jackson Laboratory, Bar Harbor, Maine 04609, USA;
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9
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Utami KH, Hillmer AM, Aksoy I, Chew EGY, Teo ASM, Zhang Z, Lee CWH, Chen PJ, Seng CC, Ariyaratne PN, Rouam SL, Soo LS, Yousoof S, Prokudin I, Peters G, Collins F, Wilson M, Kakakios A, Haddad G, Menuet A, Perche O, Tay SKH, Sung KWK, Ruan X, Ruan Y, Liu ET, Briault S, Jamieson RV, Davila S, Cacheux V. Detection of chromosomal breakpoints in patients with developmental delay and speech disorders. PLoS One 2014; 9:e90852. [PMID: 24603971 PMCID: PMC3946304 DOI: 10.1371/journal.pone.0090852] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/04/2014] [Indexed: 01/25/2023] Open
Abstract
Delineating candidate genes at the chromosomal breakpoint regions in the apparently balanced chromosome rearrangements (ABCR) has been shown to be more effective with the emergence of next-generation sequencing (NGS) technologies. We employed a large-insert (7-11 kb) paired-end tag sequencing technology (DNA-PET) to systematically analyze genome of four patients harbouring cytogenetically defined ABCR with neurodevelopmental symptoms, including developmental delay (DD) and speech disorders. We characterized structural variants (SVs) specific to each individual, including those matching the chromosomal breakpoints. Refinement of these regions by Sanger sequencing resulted in the identification of five disrupted genes in three individuals: guanine nucleotide binding protein, q polypeptide (GNAQ), RNA-binding protein, fox-1 homolog (RBFOX3), unc-5 homolog D (C.elegans) (UNC5D), transmembrane protein 47 (TMEM47), and X-linked inhibitor of apoptosis (XIAP). Among them, XIAP is the causative gene for the immunodeficiency phenotype seen in the patient. The remaining genes displayed specific expression in the fetal brain and have known biologically relevant functions in brain development, suggesting putative candidate genes for neurodevelopmental phenotypes. This study demonstrates the application of NGS technologies in mapping individual gene disruptions in ABCR as a resource for deciphering candidate genes in human neurodevelopmental disorders (NDDs).
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Affiliation(s)
- Kagistia H. Utami
- Human Genetics, Genome Institute of Singapore, Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Axel M. Hillmer
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Irene Aksoy
- Stem Cells and Developmental Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Elaine G. Y. Chew
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Audrey S. M. Teo
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Zhenshui Zhang
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Charlie W. H. Lee
- Computational and Mathematical Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Pauline J. Chen
- Computational and Mathematical Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Chan Chee Seng
- Scientific & Research Computing, Genome Institute of Singapore, Singapore, Singapore
| | - Pramila N. Ariyaratne
- Computational and Mathematical Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Sigrid L. Rouam
- Computational and Mathematical Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Lim Seong Soo
- Human Genetics, Genome Institute of Singapore, Singapore, Singapore
| | - Saira Yousoof
- Eye and Developmental Genetics Research, The Children’s Hospital at Westmead, Children’s Medical Research Institute and Save Sight Institute, Sydney, New South Wales, Australia
- Disciplines of Paediatrics and Child Health and Genetic Medicine, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Ivan Prokudin
- Eye and Developmental Genetics Research, The Children’s Hospital at Westmead, Children’s Medical Research Institute and Save Sight Institute, Sydney, New South Wales, Australia
- Disciplines of Paediatrics and Child Health and Genetic Medicine, Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Gregory Peters
- Department of Cytogenetics, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
| | - Felicity Collins
- Department of Clinical Genetics, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
| | - Meredith Wilson
- Department of Clinical Genetics, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
| | - Alyson Kakakios
- Department of Immunology, The Children’s Hospital at Westmead, Sydney, New South Wales, Australia
| | | | - Arnaud Menuet
- Service de Genetique INEM UMR7355 CNRS-University, Centre Hospitalier Régional d’Orléans, Orléans, France
| | - Olivier Perche
- Service de Genetique INEM UMR7355 CNRS-University, Centre Hospitalier Régional d’Orléans, Orléans, France
| | - Stacey Kiat Hong Tay
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ken W. K. Sung
- Computational and Mathematical Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Xiaoan Ruan
- Genome Technology and Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Yijun Ruan
- Genome Technology and Biology, Genome Institute of Singapore, Singapore, Singapore
| | - Edison T. Liu
- Cancer Therapeutics and Stratified Oncology, Genome Institute of Singapore, Singapore, Singapore
| | - Sylvain Briault
- Service de Genetique INEM UMR7355 CNRS-University, Centre Hospitalier Régional d’Orléans, Orléans, France
| | - Robyn V. Jamieson
- Eye and Developmental Genetics Research, The Children’s Hospital at Westmead, Children’s Medical Research Institute and Save Sight Institute, Sydney, New South Wales, Australia
| | - Sonia Davila
- Human Genetics, Genome Institute of Singapore, Singapore, Singapore
| | - Valere Cacheux
- Human Genetics, Genome Institute of Singapore, Singapore, Singapore
- * E-mail:
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10
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Nagarajan N, Bertrand D, Hillmer AM, Zang ZJ, Yao F, Jacques PÉ, Teo ASM, Cutcutache I, Zhang Z, Lee WH, Sia YY, Gao S, Ariyaratne PN, Ho A, Woo XY, Veeravali L, Ong CK, Deng N, Desai KV, Khor CC, Hibberd ML, Shahab A, Rao J, Wu M, Teh M, Zhu F, Chin SY, Pang B, So JBY, Bourque G, Soong R, Sung WK, Tean Teh B, Rozen S, Ruan X, Yeoh KG, Tan PBO, Ruan Y. Whole-genome reconstruction and mutational signatures in gastric cancer. Genome Biol 2012; 13:R115. [PMID: 23237666 PMCID: PMC4056366 DOI: 10.1186/gb-2012-13-12-r115] [Citation(s) in RCA: 114] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 12/13/2012] [Indexed: 12/13/2022] Open
Abstract
Background Gastric cancer is the second highest cause of global cancer mortality. To explore the complete repertoire of somatic alterations in gastric cancer, we combined massively parallel short read and DNA paired-end tag sequencing to present the first whole-genome analysis of two gastric adenocarcinomas, one with chromosomal instability and the other with microsatellite instability. Results Integrative analysis and de novo assemblies revealed the architecture of a wild-type KRAS amplification, a common driver event in gastric cancer. We discovered three distinct mutational signatures in gastric cancer - against a genome-wide backdrop of oxidative and microsatellite instability-related mutational signatures, we identified the first exome-specific mutational signature. Further characterization of the impact of these signatures by combining sequencing data from 40 complete gastric cancer exomes and targeted screening of an additional 94 independent gastric tumors uncovered ACVR2A, RPL22 and LMAN1 as recurrently mutated genes in microsatellite instability-positive gastric cancer and PAPPA as a recurrently mutated gene in TP53 wild-type gastric cancer. Conclusions These results highlight how whole-genome cancer sequencing can uncover information relevant to tissue-specific carcinogenesis that would otherwise be missed from exome-sequencing data.
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11
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Yao F, Ariyaratne PN, Hillmer AM, Lee WH, Li G, Teo ASM, Woo XY, Zhang Z, Chen JP, Poh WT, Zawack KFB, Chan CS, Leong ST, Neo SC, Choi PSD, Gao S, Nagarajan N, Thoreau H, Shahab A, Ruan X, Cacheux-Rataboul V, Wei CL, Bourque G, Sung WK, Liu ET, Ruan Y. Long span DNA paired-end-tag (DNA-PET) sequencing strategy for the interrogation of genomic structural mutations and fusion-point-guided reconstruction of amplicons. PLoS One 2012; 7:e46152. [PMID: 23029419 PMCID: PMC3461012 DOI: 10.1371/journal.pone.0046152] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 08/28/2012] [Indexed: 01/23/2023] Open
Abstract
Structural variations (SVs) contribute significantly to the variability of the human genome and extensive genomic rearrangements are a hallmark of cancer. While genomic DNA paired-end-tag (DNA-PET) sequencing is an attractive approach to identify genomic SVs, the current application of PET sequencing with short insert size DNA can be insufficient for the comprehensive mapping of SVs in low complexity and repeat-rich genomic regions. We employed a recently developed procedure to generate PET sequencing data using large DNA inserts of 10–20 kb and compared their characteristics with short insert (1 kb) libraries for their ability to identify SVs. Our results suggest that although short insert libraries bear an advantage in identifying small deletions, they do not provide significantly better breakpoint resolution. In contrast, large inserts are superior to short inserts in providing higher physical genome coverage for the same sequencing cost and achieve greater sensitivity, in practice, for the identification of several classes of SVs, such as copy number neutral and complex events. Furthermore, our results confirm that large insert libraries allow for the identification of SVs within repetitive sequences, which cannot be spanned by short inserts. This provides a key advantage in studying rearrangements in cancer, and we show how it can be used in a fusion-point-guided-concatenation algorithm to study focally amplified regions in cancer.
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Affiliation(s)
- Fei Yao
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
- Department of Epidemiology and Public Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Pramila N. Ariyaratne
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Axel M. Hillmer
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Wah Heng Lee
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Guoliang Li
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Audrey S. M. Teo
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Xing Yi Woo
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Zhenshui Zhang
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Jieqi P. Chen
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Wan Ting Poh
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Kelson F. B. Zawack
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Chee Seng Chan
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - See Ting Leong
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Say Chuan Neo
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Poh Sum D. Choi
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Song Gao
- Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences, National University of Singapore, Singapore, Singapore
| | - Niranjan Nagarajan
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Hervé Thoreau
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Atif Shahab
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Xiaoan Ruan
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Valère Cacheux-Rataboul
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Chia-Lin Wei
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Guillaume Bourque
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Wing-Kin Sung
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Edison T. Liu
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Yijun Ruan
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- * E-mail:
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12
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Hillmer AM, Yao F, Inaki K, Lee WH, Ariyaratne PN, Teo ASM, Woo XY, Zhang Z, Zhao H, Ukil L, Chen JP, Zhu F, So JBY, Salto-Tellez M, Poh WT, Zawack KFB, Nagarajan N, Gao S, Li G, Kumar V, Lim HPJ, Sia YY, Chan CS, Leong ST, Neo SC, Choi PSD, Thoreau H, Tan PBO, Shahab A, Ruan X, Bergh J, Hall P, Cacheux-Rataboul V, Wei CL, Yeoh KG, Sung WK, Bourque G, Liu ET, Ruan Y. Comprehensive long-span paired-end-tag mapping reveals characteristic patterns of structural variations in epithelial cancer genomes. Genome Res 2011; 21:665-75. [PMID: 21467267 DOI: 10.1101/gr.113555.110] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Somatic genome rearrangements are thought to play important roles in cancer development. We optimized a long-span paired-end-tag (PET) sequencing approach using 10-Kb genomic DNA inserts to study human genome structural variations (SVs). The use of a 10-Kb insert size allows the identification of breakpoints within repetitive or homology-containing regions of a few kilobases in size and results in a higher physical coverage compared with small insert libraries with the same sequencing effort. We have applied this approach to comprehensively characterize the SVs of 15 cancer and two noncancer genomes and used a filtering approach to strongly enrich for somatic SVs in the cancer genomes. Our analyses revealed that most inversions, deletions, and insertions are germ-line SVs, whereas tandem duplications, unpaired inversions, interchromosomal translocations, and complex rearrangements are over-represented among somatic rearrangements in cancer genomes. We demonstrate that the quantitative and connective nature of DNA-PET data is precise in delineating the genealogy of complex rearrangement events, we observe signatures that are compatible with breakage-fusion-bridge cycles, and we discover that large duplications are among the initial rearrangements that trigger genome instability for extensive amplification in epithelial cancers.
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Affiliation(s)
- Axel M Hillmer
- Genome Technology and Biology, Genome Institute of Singapore, Singapore 138672, Singapore
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13
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Shek LPC, Chong AR, Soh SE, Cheong N, Teo ASM, Yi FC, Giam YC, Chua KY, Van Bever HP. Specific profiles of house dust mite sensitization in children with asthma and in children with eczema. Pediatr Allergy Immunol 2010; 21:e718-22. [PMID: 20337963 DOI: 10.1111/j.1399-3038.2010.01019.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sensitization to house dust mites (HDM) is highly prevalent among the young atopic population in Singapore. Previously published data suggest that individuals with skin allergies show preferred sensitization to Dermatophagoides pteronyssinus while individuals with pure respiratory allergies show preferred sensitization to Blomia tropicalis. The aim of our study was to compare the sensitization profiles between children with asthma and those with eczema to D. pteronyssinus and B. tropicalis and their specific allergens. A total of 60 children, 30 with asthma and 30 with eczema were recruited. IgE levels specific for a panel of HDM allergens from the two mite species were measured using enzyme-linked immunosorbent assay. The asthma group showed highest sensitization to Blo t5 while the eczema group showed highest sensitization to Der p5. Comparison between the two disease groups showed that the eczema group had significantly higher IgE levels for Der p (p = 0.042) and its allergens Der p1 (p = 0.019) and Der p5 (p = 0.001). Generally, the eczema group was more sensitized to the panel of allergens compared to the asthma group. Individuals with asthma and those with eczema showed different sensitization profiles to HDM. These findings highlighted possible mechanisms for different manifestation of allergy.
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14
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Teo ASM, Ramos JDA, Lee BW, Cheong N, Chua KY. Expression of the Blomia tropicalis paramyosin Blo t 11 and its immunodominant peptide in insect cells. Biotechnol Appl Biochem 2006; 45:13-21. [PMID: 16584386 DOI: 10.1042/ba20050239] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Blo t 11, a dust-mite (Blomia tropicalis) paramyosin, is an allergen with significant IgE reactivity that has potential as a diagnostic/therapeutic reagent for house-dust-mite allergy. The present study describes the successful expression of Blo t 11 and its immunodominant peptide fD in insect cells using a baculovirus expression system. The Blo t 11 and fD genes were cloned into the pMelBacA vector and the resulting vectors were co-transfected into Sf9 insect cells with Bac-N-Blue DNA. Plaque assay was used to select for recombinant virus that was then used to infect High Five insect cells for protein expression. Secreted proteins were harvested by immuno-affinity purification using monoclonal antibodies to Blo t 11. Purified proteins were analysed by immunoblotting, N-terminal sequencing and ELISA. Immunoblot analyses revealed the full-length Blo t 11 cDNA expressed as a minor protein band of approx. 200 kDa and two major protein bands of approx. 60 and 70 kDa. Clones expressing fD cDNA fragment produced a protein of approx. 30 kDa that was confirmed to be fD by N-terminal sequencing. Approx. 4-7.5 mg/l of fD and 1 mg/l of Blo t 11 were obtained by affinity purification. ELISA results showed that human IgE reactivity to these recombinant allergens was lower as compared with that of the native Blo t 11, suggesting that these baculovirus-expressed allergens exhibiting reduced allergenicity could be useful for the development of immunotherapeutic reagents for mite allergy.
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Affiliation(s)
- Audrey S M Teo
- Bioprocessing Technology Institute, A*STAR (Agency for Science, Technology and Research), Singapore
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15
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Ramos JDA, Teo ASM, Lee BW, Cheong N, Chua KY. DNA immunization for the production of monoclonal antibodies to Blo t 11, a paramyosin homolog from Blomia tropicalis. Allergy 2004; 59:539-47. [PMID: 15080836 DOI: 10.1046/j.1398-9995.2003.00409.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Blo t 11 is a high molecular weight allergen from Blomia tropicalis with significant immunoglobulin (Ig)E binding frequency. Native and recombinant Blo t 11 are susceptible to degradation and the isolation and expression of the allergen is problematic thus obtaining sufficient amounts of purified Blo t 11 for antibody production is limiting. DNA-based immunization is an attractive alternative strategy that bypasses antigen purification for antibody production. OBJECTIVES To use a DNA-based immunization protocol for the production and characterization of Blo t 11 monoclonal antibodies (mAbs). METHODS The 2625 bp cDNA coding for Blo t 11 was cloned into a mammalian expression vector and immunized intramuscularly with electroporation into mice. Monoclonal antibodies to Blo t 11 were generated using a methylcellulose-based hybridoma cloning kit. These mAbs were utilized for native Blo t 11 isolation and the development of sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS Six mAbs recognizing the native and recombinant Blo t 11 were generated and characterized. Native Blo t 11 was affinity purified from Bt extract and its identity was confirmed by matrix assisted laser desorption/ionization - time of flight mass spectrometry. The native Blo t 11 showed IgE reactivity with 67% of mite allergic sera. A two-site ELISA developed showed a detection limit of 100 pg/ml of Blo t 11. CONCLUSION A DNA-based immunization protocol was successfully used to generate Blo t 11 mAbs with a spectrum of distinct epitopes located throughout the whole molecule, and they are useful for immunoaffinity purification and immunoassays.
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Affiliation(s)
- J D A Ramos
- Department of Paediatrics, National University of Singapore, Singapore
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16
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Ramos JDA, Cheong N, Teo ASM, Kuo IC, Lee BW, Chua KY. Production of monoclonal antibodies for immunoaffinity purification and quantitation of Blo t 1 allergen in mite and dust extracts. Clin Exp Allergy 2004; 34:604-10. [PMID: 15080814 DOI: 10.1111/j.1365-2222.2004.1922.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Blo t 1 is a cysteine protease-like allergen from Blomia tropicalis. Recombinant Blo t 1 binds up to 90% of IgE from allergic patients and shows limited cross-reactivity to Der p 1. The generation of monoclonal antibodies (mAbs) against Blo t 1 is important for the detection, isolation and characterization of the native form of the allergen. METHODS Mice were immunized intramuscularly with naked plasmid DNA encoding Blo t 1 gene with in vivo electroporation and boosted intraperitoneally with recombinant Blo t 1. mAbs against Blo t 1 were generated using a methylcellulose-based hybridoma cloning kit. The native Blo t 1 was isolated by mAb affinity purification and its allergenicity was determined by ELISA. A two-site ELISA for Blo t 1 was developed using the mAbs generated. RESULTS A DNA-based immunization protocol induced high titre Blo t 1-specific antibodies in mice. Six stable hybridoma clones secreting mAbs recognizing the native and recombinant Blo t 1 were generated. The native Blo t 1 was affinity-purified from a B. tropicalis extract and its allergenicity was determined at 63% using a panel of Singaporean and Malaysian mite allergic patients' sera. A two-site ELISA was developed, which showed a detection limit of 10 ng/mL of Blot t 1. CONCLUSION Six Blo t 1 mAbs were successfully generated by DNA immunization. These mAbs are useful for nBlo t 1 immunoaffinity isolation and quantitative immunoassays for Blo t 1 in mite and environmental dust extracts.
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Affiliation(s)
- J D A Ramos
- Department of Paediatrics, National University of Singapore, Singapore
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17
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Ramos JDA, Teo ASM, Ou KL, Tsai LC, Lee BW, Cheong N, Chua KY. Comparative allergenicity studies of native and recombinant Blomia tropicalis Paramyosin (Blo t 11). Allergy 2003; 58:412-9. [PMID: 12752328 DOI: 10.1034/j.1398-9995.2003.00106.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND The complementary DNA (cDNA) encoding for Blo t 11, a 102 kD allergen from Blomia tropicalis (Bt) was isolated, expressed and characterized previously. This study aimed to isolate the native Blo t 11 allergen and compare its allergenicity with the recombinant forms. METHODS Native Blo t 11 (nBlo t 11) was isolated from crude Bt extract by immuno-affinity chromatography, analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blot, and verified by MALDI-TOF MS. Recombinant full-length Blo t 11 (rFL-Blo t 11) and its immunodominant peptide (fD) were expressed as glutathione S-transferase (GST)-fusion proteins in Escherichia coli. Immunoglobulin E (IgE) reactivity of the Blo t 11 allergens were determined by enzyme-linked immunosorbent assay (ELISA) and skin prick test. The inhibition capacity of the nBlo t 11 against fD and vice versa was determined by absorption studies. RESULTS Affinity purified nBlo t 11 was susceptible to degradation with the major degraded product resolved at approximately 66 kD. The nBlo t 11 was confirmed by immunoblot analysis and MALDI-TOF MS that generated 13 peptides with complete identity to the deduced amino acid sequence of Blo t 11. Comparative in vitro and in vivo allergenicity tests and the cross inhibition studies between the native and recombinant Blo t 11 showed that recombinant fD, but not the rFL-Blo t 11, has comparable IgE reactivity with the native counterpart. CONCLUSIONS This comparative study confirmed that the recombinant peptide fD contains the main immunodominant region of Blo t 11. This recombinant peptide, instead of the full-length protein, is a good candidate for diagnostic and therapeutics development for mite allergy.
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Affiliation(s)
- J D A Ramos
- Department of Paediatrics, Faculty of Medicine, National University of Singapore, Singapore
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